Gerlt Technologies makes hundreds of customizable rack effects, at prices comparable to guitar pedals.  It's time to dump that pedal board and get Your Tone off the floor!


 What We Do

You know them as guitar pedals

We build them as rack effect modules you can customize to get Your Tone

Put several rack effect modules into a 3U rack enclosure

Connect power and audio on the back like guitar pedals, adding connections for remote switching

Add a remote footswitch unit to turn rack effects on and off

Add as many rack effect modules, enclosures, and third-party products as you like. Plug in your guitar and amp. Rock it! It's that simple.


Quick Hits:

  • Check out our GT Effects Overview to see why we do this

  • Check out our Compares To charts to see the full list of effects we offer

  • Follow the menus from Products, to Modules, to Modules By Type to get a list of our effect types.  Select any effect type to get a list of all our effects of that type.  Select any effect to get full information including pricing.



Hello Effects Fans!

In my last update I was excited after finding some small quantities of critical components that are needed to build our effects. I hoped that to be a sign that perhaps some of our supply chain problems were easing. But it seems those were just one-off lucky finds. I haven’t found any more since then. On top of all the other problems, we now have the ripple effect of the conflict in the Ukraine, which has caused even more parts to become unavailable and/or very expensive.

It’s one thing to be optimistic, but another to be unrealistic. This is no longer a time for simple optimism. It is a time for handling unpleasant realities. Our reality is that it seems very unlikely that enough positive changes will occur quickly enough for us to re-open in 2022. While the corporation is in a good position to weather a continued lengthy shutdown, the people are not able to. We need to take some time to go do “other stuff” for a while.

We still have several new modules to announce. The work is complete on almost all of them, so I’ll try to get those announcements out in April and May. Other than that, I’m afraid it is going to be pretty quiet here until we are able to reliably source parts at reasonable prices again. I probably won’t have another update until late summer or into autumn.

The good news is that Gerlt Technologies is still here and alive. We haven’t “lost” anything. We still have the largest selection of rack effects available, getting close to 400. Our effects still sound great. And we still want to make them available to you. We’re just going to have to continue our break for a while until the business and economic conditions improve to the point that we can provide outstanding products and support at affordable prices.

I apologize for the continued delay and will do everything I can to get us going again as soon as it becomes feasible.



Bill Gerlt

President, Gerlt Technologies

Dallas, Texas

11 April, 2022




We’re happy to announce the addition of the Teledrive module to our product line.  The Teledrive compares to the Nobels ODR-1.  The Teledrive is a transparent boost to mild overdrive, similar in function (but not design) to other transparent overdrives such as the Klon Centaur or Maxon GT 820.  It is probably at its best pushing a tube amp into breakup. 

The ODR-1 was originally a German pedal, but is now produced in China.  The current Chinese version is very similar to the original pedal circuit.  The originals were inconsistent in the transistors and op amps that were used.  In addition to these minor production differences, one production run had some controls connected incorrectly, causing a significant degradation in tone.  The pedal was produced for quite a long time, but didn’t achieve widespread fame, possibly due to the inconsistent performance.  But some people, particularly in the Nashville “in crowd” discovered that this pedal could be outstanding if you got “a good one”.  It has apparently been a contributor to the Nashville “more Telecaster” sound for some time.

The pedal went out of production for a while, but is back again.  The unusual op amp has been replaced with a standard 4558D op amp, very similar in sound to the original.  The transistors still seem to be of various types, but again, still very similar in sound and feel to the original.  Oddly, though produced in China, the new pedals still use through-hole components instead of surface mount – nice.

The circuit is fairly transparent, but maybe tuned for brighter instruments, such as the Telecaster.  With other guitars, it can seem a little bassy unless you dial the tone up a bit.  Mostly though, it just gives you more of what you’ve got, nice for pushing a tube amp a bit harder.  Both the original pedals and our Teledrive can pick up a bit of noise with the Volume and Gain up, along with the Spectrum dialed to the treble side.  That’s true of most boost and gain pedals, though.

We added a couple of options, you can check out on the Teledrive page in the Overdrive modules list.  One is a Bass Cut to handle what some might consider a bit much bass.  Another is the Plus option, which like the Plus version of the original pedal provides a switchable boost that increases gain and tweaks the tone range to have a bit less bass.  The original circuit uses silicon clipping diodes, which can put a bit of compression on the tone.  If you want to trim the gain and compression slightly, we allow clipping diodes choices so that you can try red LEDs or other clipping configurations. 

If you are looking for a boost or transparent overdrive, something similar to the Unicorn or GT 820, check out the Teledrive.